1. Field of the Invention
The present invention relates to a combustion device, and more particularly to a combustion device used in conjunction with solid or liquid fuel contained in a vessel.
2. Description of the Prior Art
Combustion devices have long been used to provide both heat and illumination. Traditionally, conventional candles constructed of solidified paraffin having a textile wick extending therethrough were used to provide this needed heat and illumination. These candles, however, tend to be messy, the candles often burning unevenly or becoming extinguished and wax dripping down the candles to solidify on supports for the candles. Moreover, the flames produced by these conventional candles are not adjustable, the amount of heat and illumination supplied by the candle being fixed, for the most part.
To remedy these shortcomings of the conventional candle, alternative combustion devices have been created that float atop solid or liquid fuels such as paraffin that provide even burning and reduce the wasting of unused fuel. While several such combustion devices are known, none has provided high efficiency and convenient adjustability of flame intensity.
One such combustion device is shown in U.S. Pat. No. 397,011 issued Jan. 29, 1889 to Jean Antoine Hubert Leynen-Hougaerts. In this patent, a lamp is described that utilizes a capsule which floats atop the surface of vegetable oil contained in a tubular vessel. The capsule, as described in the specification, is preferably fabricated of glass and has a central tube through which small quantities of the oil may pass for combustion. The capsule is weighted such that the level of the oil surface will be flush with the upper edge of the central tube, assuring sufficient supply of oil to the flame. In use, the upper edge of the central tube is heated until the tube becomes sufficiently hot to cause the oil within the tube to boil, thus becoming combustible and thereafter catching fire. Although the lamp adequately burns the oil to produce a flame, use of the lamp is limited. One such limitation is that the lamp can only use liquid fuels such as vegetable oils. Solid fuels such as solid paraffin, which tend to burn more cleanly and with less residue, may not be used with the design. In addition, when liquid fuels of different specific gravities are used, capsules of different masses must be employed to ensure that the oil surface is level with the top edge of the central tube.
Another prior art design is discussed in U.S. Pat. No. 1,184,511 issued May 23, 1916 to Henry J. Bourgeois. Similar to the Leynen-Hougaerts patent, this design uses liquid fuels to produce artificial light. In the Bourgeois design, a semi-rigid fibrous wick travels through a capillary tube centrally configured within an airtight float, the wick supplying fuel to the ignition area. To accommodate liquid fuels of different specific gravities, the capillary tube is longitudinally adjustable within the float, maintaining an ignition point sufficiently elevated above the surface of the fuel. As with the Leynen-Hougaerts patent, this design may only be used with liquid fuels; no provision is made for the combustion of solid fuel.
Yet another configuration is shown in U.S. Pat. Nos. 4,013,397 and 4,234,303 issued to Fernando M. Neugart on Mar. 22, 1977 and Nov. 18, 1980 respectively. In these patents, a combustion apparatus is disclosed which is configured to set atop the surface of a solid mass of fuel contained in a vessel. The combustion apparatus is formed of two plate members fabricated from a highly conductive metal which form a airtight compartment to provide buoyancy. Extending upwardly through an aperture in the center of the apparatus is a fibrous wick, in one embodiment supported by a thin support member. In use, the plate structure allows for the transfer of heat from the flame to the surface of the solidified fuel, thereby melting fuel, thus allowing the apparatus to float atop a shallow pool of molten fuel. The wick then draws from this pool of fuel maintaining a constant supply of fuel to the flame. While improving upon the state of the art, neither of these designs provide for adjustment of the flame intensity.
A lamp employing a wick support which has a metal, heat conducting ring and maintains a level of liquified wax at the same level as the ring is seen in U.S. Pat. No. 5,193,994, issued Mar. 16, 1994 to Hans-Ludwig Schirneker. The wick and support ride down upon a solid candle as the paraffin body of the candle is consumed and the device is not designed to be used interchangeably with either liquid or solid fuel.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.